Amygdala efferents form inhibitory-type synapses with a subpopulation of catecholaminergic neurons in the rat Nucleus tractus solitarius.
Amygdala efferents form inhibitory-type synapses with a subpopulation of catecholaminergic neurons in the rat Nucleus tractus solitarius.
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杏仁核传出神经与大鼠孤束核中的儿茶酚胺能神经元亚群形成抑制型突触。
DOI：
10.1002/cne.903620406
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Cestari,DM
中科院分区：
文献类型：
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作者：
Pickel,VM;vanBockstaele,EJ;Chan,J;Cestari,DM
杏仁中央核（CNA）整合内脏反应的压力部分通过传出投射到部分内侧核的孤束（mNTS）含有儿茶酚胺能神经元。为了确定这些神经元的CNA调节的解剖学位点，在成年大鼠mNTS中，将顺行转运的菜豆白细胞凝集素（PHA-L）或生物素化葡聚糖胺（BDA）的免疫过氧化物酶检测与儿茶酚胺合成酶酪氨酸羟化酶的免疫金银标记相结合。在中间mNTS内鉴定的350个顺行标记的终末中，30%形成对称的抑制型突触，其余的缺乏可识别的连接，如在单个截面内所见。在形成对称性突触的终末中，16%的终末与酪氨酸羟化酶免疫反应阳性树突形成突触前，其余的终末与未标记树突形成突触前。通过金-银颗粒密度评估的酪氨酸羟化酶免疫反应性水平在接受来自CNA传出神经的突触输入的树突中显著低于相同大小的树突（2.平均面积0 μ m2），接受来自未标记终末的突触或缺乏可识别的突触输入。当不考虑传入输入单独检查时，平均横截面积为1-3 μ 2 m的中型和大型树突也比小型（<1 μ 2 m）树突含有显著更少的酪氨酸羟化酶免疫反应性。这些结果表明，到mNTS的CNA传出抑制不含儿茶酚胺的神经元和以其低水平酪氨酸羟化酶区分的儿茶酚胺能神经元亚群。研究结果还表明，小，可能更远，树突在中间mNTS可能合成和/或释放儿茶酚胺。© 1995 Wiley利斯公司
The central nucleus of the amygdala (CNA) integrates visceral responses to stress partially through efferent projections to portions of the medial nuclei of the solitary tracts (mNTS) containing catecholaminergic neurons. To determine anatomical sites for CNA modulation of these neurons, immunoperoxidase detection of anterogradely transportedPhaseolus vulgarisleucoagglutinin (PHA‐ L) or biotinylated dextran amine (BDA) was combined with immunogold silver labeling of the catecholamine‐synthesizing enzyme, tyrosine hydroxylase, in adult rat mNTS. From 350 anterogradely labeled terminals identified within the intermediate mNTS, 30% formed symmetric, inhibitory‐type synapses and the remainder lacked recognized junctions as seen within a single plane of section. Of the terminals forming symmetric synapses, 16% were presynaptic to tyrosine hydroxylase immunoreactive dendrites and the remainder to unlabeled dendrites. The level of tyrosine hydroxylase immunoreactivity as assessed by density of gold‐silver particles was significantly lower in dendrites receiving synaptic input from CNA efferents as compared with dendrites of the same sizes (2. 0 μm2in mean area) which received synapses from unlabeled terminals or lacked recognizable synaptic inputs. When separately examined without regard to afferent input, the medium‐ and larger‐sized dendrites having mean cross‐sectional areas of 1–3 μ2m also contained significantly less tyrosine hydroxylase immunoreactivity than small (<1 μ2m) dendrites. These results suggest that CNA efferents to the mNTS inhibit non‐catecholamine‐containing neurons and a subpopulation of catecholamin ergic neurons distinguished by their low levels of tyrosine hydroxylase. The findings also indicate that small, presumably more distal, dendrites in the intermediate mNTS may synthesize and/or release catecholamines. © 1995 Wiley‐Liss Inc.